Nobiletin Inhibits Cell Viability via the SRC/AKT/STAT3/YY1AP1 Pathway in Human Renal Carcinoma Cells

Abstract

Nobiletin is a polymethoxy flavonoid isolated from Citrus depressa and Citrus reticulata. It has been reported that nobiletin can suppress tumors. We primarily explored the antitumor effects of nobiletin and the associated potential mechanisms in ACHN and Caki-2 renal carcinoma cells. A CCK-8 assay and cloning experiments were used to assess cell viability, and a transwell assay and scratch test were used to assess metastatic ability. The cell cycle was analyzed by flow cytometry, whereas apoptosis was analyzed using flow cytometry and a terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay. Protein expression was examined by Western blot and immunofluorescence. Renal cancer cells were subcutaneously transplanted into nude mice for in vivo studies. The data showed that nobiletin administration significantly dose-and time-dependently suppressed renal cancer cell proliferation; moreover, nobiletin treatment induced cell cycle arrest in the G0/G1 phase and promoted apoptosis. Immunofluorescence analysis indicated that nobiletin decreased the nuclear localization of signal transducer and activator of transcription 3 (STAT3) and YY1-associated protein 1 (YY1AP1). Western blot showed that the levels of phosphorylated SRC, phosphorylated AKT serine/threonine kinase (AKT), and phosphorylated STAT3 were decreased, whereas that of phosphorylated YY1AP1 was increased. The results further showed that application of insulin-like growth factor 1 (IGF1) was able to reverse the nobiletin-induced changes in the levels of phosphorylated AKT, phosphorylated STAT3, and phosphorylated YY1AP1, and could also reverse the antitumor effects of nobiletin. The results of in vivo experiments showed that, compared to the control, tumor volume and weight were both reduced following nobiletin treatment. In conclusion, our study demonstrated that nobiletin can inhibit renal carcinoma cell viability and provides a novel therapeutic approach for the treatment of kidney cancer.

Nobiletin Affects Circadian Rhythms and Oncogenic Characteristics in a Cell-Dependent Manner

“…30 We also found decreased colony areas at the highest concentration tested. Colony formation assays in other cancer cell lines such as ACHN and Caki2, showed that nobiletin dose-dependently reduced colony numbers at concentrations up to 120 µM, 18 and colony numbers of H460 non-small cell lung cancer cells at 50 µM. 50 Interestingly, in our study, we found that nobiletin yields different circadian and anti-cancer effects depending on cell line.…”

“…15 It also reduced cell adhesion, invasion, and migration in the highly metastatic AGS gastric adenocarcinoma cell line, 16 suppressed viability of PC-3 and DU-145 prostate cancer cell lines, 17 and inhibited ACHN and Caki-2 renal carcinoma cell proliferation by cell cycle arrest in G0/G1 phase. 18 Also, nobiletin causes anti-leukemic effects in HL-60 human acute myeloid leukemia cells, 19 reduction of proliferation and migration in U87 glioma cells, 20 and decreases cell proliferation in the low tumor-grade MCF7 cell line via G1 cell cycle block. 21 It may induce apoptosis and inhibit cell migration via MAPK and/or MAPK/AKT related pathways.…”

Suppressing the metastatic properties of the breast cancer cells using STAT3 decoy oligodeoxynucleotides: A promising approach for eradication of cancer cells by differentiation therapy

“…Investigations revealed that either inhibition of STAT3 activity or translocation to cell nucleus suppresses tumor growth by induction of cell cycle arrest and promotion of apoptosis (J. Li et al, ; Wei et al, ). Our data on decoy treatment also led to antiproliferation and cell cycle arrest at G 0 /G 1 transition to the S phase, which decreased S‐ and G 2 /M phase percentage and subsequently cell proliferation.…”

Nobiletin, a citrus polymethoxyflavone, enhances the effects of bicalutamide on prostate cancer cellsviadown regulation of NF-κB, STAT3, and ERK activation

“…39 NBT exhibited activity of inhibit cancer cells viability, migration and angiogenesis via regulating STAT3 expression. 40,41 Besides, the interaction between STAT3 and NF-kB plays a crucial role in the tumorigenesis, 32 targeting STAT3 and NF-kB offer new chemotherapeutic approaches. In our study, the combination treated with NBT and BCT not only show great inhibit in NF-kB but also in the expression of p-STAT3/STAT3.…”